LG LT-15A10, LE-15A10, LL-15A10 User Manual

Welcome to

LG LCD TV

LE-15A10 LL-15A10

Europe

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LT-15A10

China

Asia

Canada

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Taiwan

Philippines

Austria

Contents

1. LCD Technology

1) What is TFT LCD ?

2) Structure of TFT LCD

3) TFT-LCD Operating Mechanism

4) Operating Theor y

5) Structure LCD Module

6) Structure of Back light

7) Function of Back light

8) Key Parts ; Color Filter, Polarizer

2. LCD Market Trend

(1) Comparison with other Displa y devices (2) World Display Market Trend (3) LCD TV Market trend (4) Guidance of handling LCD product (5) Abbreviations

3. LCD TV Structure

(1) General Specifications (2) Presentation for SVC Engineer

1. LCD Technology

1) What is TFT LCD ?

2) Structure of TFT LCD

3) TFT-LCD Operating Mechanism

4) Operating Theor y

5) Structure LCD Module

6) Structure of Back light

7) Function of Back light

8) Key Parts ; Color Filter, Polarizer

What is TFT(Thin Film Transistor)?

TRANSISTOR

(MOS-FET)

DRAIN

GATE

SOURCE

When supply over certain voltage(Vth) to the GATE, it delivers information from Drain to Source

SWITCHING Characteristics

TFT Panel

TFT Element

TFT

DRAIN

GATE

SOURCE

TPE

Compound Transistor with thin film in every Pixel on ITO.

Independent on neighboring Pixel

TFT Cross section

Semi-Conductor

Insulator

Transparent Pixel Electrode

SOURCE DRAIN

GATE

Glass Panel

Structure of TFT- LCD

% (Approx....)

300

One Pixel

)

Common Electrode

)

Pixel Electrode

Data Line Gate Line

! Liquid Crystal

Control the amount of light by the Applying Voltage

C/F Glass

TFT Glass

TFT LCD Panel

# Source

Transport the Data Signal

Glass

+ + + +

- -

" Gate

On/Off the

TFT

Glass

Back Light

- -

$ Pixel

Applying

Voltage

to the

Liquid Crystal

Polarizer

Liquid Crystal

- - - - - -

White (TFT Off) Black (TFT On)

TFT- LCD Operating mechan is m

The structure of TFT-LCD is that Liquid Crystal is being filled betw een C/F Glass & TFT Glass. One Pixel consists of 3

sub-Pixels(R,G,B) and according to the number of the pixels, Display Resolution (SVGA,XGA,etc) is determined.

The TFT Matrix consists of Data Line(Carrying display data signal),Gate Line(Carrying signal for turn On/Off the TFT).Each TFT, on each sub-pixel, controls the amount of Applying Voltage between C/F glass electrode & TFT glass electrode for the Liquid Crystal.

The Applying Voltage changes the Direction of Liquid Crystal w hich changes direction of the Light. Transmittance rate of the Polarized Light, polarized by Polarizer, is controlled by Applying Voltage. As a conclusion, Displayed Light is now under-control of Display Data Signal.

Light(CCFL lamp)

Polarizer is a filter

Polarizer

which polarize the light to one direction.

Liquid Crystal

< Light transmittance >

< Blocking >

Polarized light

Electrode

&&&&

= off

= on

&&&&

Liquid Crystal

Electrode

< VLC = 0 > < VLC = 3.3V >

Operating Theory

(Braun Tube : Light Emitting Component) (TFT-LCD : Non-Light Emitting Component)

HEATER

Electronic Gun

Grid 1

Grid 2

Grid 3

Anode Grid 4

Deflection

Section

GLASS

Flourescent

Beam

Vacuum

Luminous

Source

Polarizer

Light(White)

COLOR FILTER

Glass Panel

Polarizer

Liquid

Crystal

Green

TFT+Electrode

Electrode

Structure of LCD Module

LCM = Case top + LCD panel

B/L Assy + Plate

Case Top

LCD Panel

Diffusers & Prisms Light Guide

Reflector Lamp

Housing Lamp

D-IC(on TCP)

PCB

Support Main

Bottom Cover

Back light Assy

Bottom Plate

Structure of LCD Module

Driving

Circuit

Bright Dark Gray

Gate Driver IC

Inverter

Power Supply

for Video Signal

Data Driver IC

Printed PCB Board

Pixel Array & Wiring

Common

Electrode

Lamp

Dn-1

Dn+1

Polarizer

CF Panel

LC TFT Panel

Polarizer

Pixel Electrode

LC Panel

Lamp

Inverter

Lamp Prism

Diffuser

Light Guide Reflector

B/L Unit

Structure of Back Light Unit

Pad

Diffuser(Protector)

Top Prism

Bottom Prism

Diffuser

Light Guide

Screw

Plate

Reflector

Supporter main

Lamp Housing

Lamp Ass

’

Function of Back Light

Structure of B ack Light

Lamp

LCD PANEL

Diffuser (Protector)

Top Prism

Bottom Prism

Diffuser

Function on each part

Display the light controlled by data signal

Same structure as bellow diffuser, Protect the top prism

Same function as bottom prism, Increase the luminanc e up to 1.3 3 ti mes o f bott o m pri s m

Concentrate the light and increase the luminance up to 1.55 times of the light guide

Uniform and concentrate the light received from light guide

Lamp Housing(Lamp Reflector)

Pattern(Dot/Shibo/V-cut)

Light guide (Flat/Wedge)

Reflector

Guide the light from lamp and uniform the light

Reflect the leakage light from light guide to reduce the loss of the light injected to the light guide

Key Parts : Color Filter

To realize color of the Display, array Red,Green & Blue color paint beneath Upper Glass Panel regularly in accord with Pixel electrode of lower Glass Panel.

! Kinds of Pixel Array

' Delta Array

( Stripe Arra y

! The Function of Color Filter

Divide the white light from luminous source into Red, Green & Blue

Pixel

White Light

) Mosaic Array

Common Electrode

Glass

BRG

Key Parts : Polarizer

A kind of filter, which polarize light one direction.

Light

Polarizer

Key Parts : Back Light

Back Light Unit,located behind TFT-Panel lower Glass, and supplies light to the PANEL.

CCFL LAMP (Cold Cathode Fluorescence Lamp)

LAMP

AC 1000V

Inverter

Direct Type

Structure

LAMP

LCD Panel

CASE

Can realize White Light Long life time(Appr. 25,000HRS) Simple Brightness control Small Size

Easy to Adhere

Side Guided Type

LCD Panel

Guide

LAMP

Reflector

Merits

Demerits

High Light Efficiency Simple Structure

Thick

Slim & Compact Size

Complicated Structure,Expensive Low Light Efficiency

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